Rapp L M, Smith S C
Cullen Eye Institute, Baylor College of Medicine, Houston, Texas 77030.
Invest Ophthalmol Vis Sci. 1992 Nov;33(12):3367-77.
The histologic manifestations of rhodopsin-mediated versus short-wavelength classes of retinal phototoxicity were compared after spectral exposures of the albino rat retina. Animals were exposed to wave-bands of light centered at the peak of rhodopsin absorbance (green, 500 nm) or in the ultraviolet A (UVA; 360 nm). Intensity-damage curves generated for each wave-band indicated that UVA light was 50-80 times more effective than green light at causing photoreceptor cell losses. Examination of early ultrastructural changes in rod inner segments, outer segments, and retinal pigment epithelium revealed a remarkable degree of similarity between UVA and green light-induced damage. Furthermore, the two classes of damage were indistinguishable in terms of post-exposure recovery from threshold damage and regional distribution of photoreceptor cell loss along the vertical meridian. The finding of essentially identical histologic manifestations for the two classes of damage raises the possibility that they share a common biochemical etiology or pathway of cell destruction.
在对白化大鼠视网膜进行光谱照射后，比较了视紫红质介导的视网膜光毒性与短波长类视网膜光毒性的组织学表现。将动物暴露于以视紫红质吸收峰值为中心的光波段（绿色，500纳米）或紫外线A（UVA；360纳米）。为每个光波段生成的强度-损伤曲线表明，UVA光在导致光感受器细胞损失方面比绿光有效50-80倍。对杆状细胞内段、外段和视网膜色素上皮早期超微结构变化的检查显示，UVA和绿光诱导的损伤之间存在显著程度的相似性。此外，就从阈值损伤的暴露后恢复以及光感受器细胞损失沿垂直子午线的区域分布而言，这两类损伤无法区分。两类损伤的组织学表现基本相同这一发现增加了它们共享共同生化病因或细胞破坏途径的可能性。
